Sera from Clinical Center AIDS patients were monitored for antibodies to Toxoplasma gondii and Entamoeba histolytica and were found to be similar to those you would find in any group of non-AIDS patients. Toxoplasma was, however, found at autopsy from a patient who died from other complications of AIDS. Seven clones producing antibody to Brugia malayi have been isolated by monoclonal antibody and are awaiting characterization and purification. The methodology to enable identification of parasite antigen in immune complexes has been explored and although still under investigation early findings indicate that it should be possible to detect antigen within complexes even those of antibody excess.